Dentifrice compositions are well known for dental and oral hygiene care. High water (e.g., >44 wt %) and high carbonate (e.g., >24 wt %) formulation chassis are cost effective for many markets and consumers. Dental plaque is a sticky, colorless deposit of bacteria that is constantly forming on the tooth surface. Saliva, food and fluids combine to produce these deposits that collect where the teeth and gums meet. Plaque buildup is the primary factor in poor oral health that can lead to caries and periodontal (gum) disease, including gingivitis. One way dentifrice compositions help prevent and control plaque is by leveraging anti-bacterial agents; however, the disadvantage and formulation challenge is the unintended reactivity of anti-bacterial agents with formulation ingredients and environment of containing calcium carbonate matrix. This may include oxidative degradation, hydrolysis, adsorption or precipitation of oxy-hydroxide species, any of which can impact the bio-availability of the anti-bacterial agent. There is a continuing need to provide such formulations that help prevent plaque formation on teeth and/or minimize the use of antimicrobial agents, particularly in high water and high carbonate dentifrice formulation chassis.
Fluoride ion sources, such as sodium monofluorophosphate, are well known for their anti-caries benefit. Fluoride uptake in dental plaque is an important metric in assessing the efficacy of anti-plaque or plaque mitigation benefits of the dentifrice compositions described herein. Fluoride is known to have the potential to exert an anti-caries benefit largely through three mechanisms; inhibition of demineralization, promotion of remineralization and interference with bacterial growth and metabolism. Small but protracted elevations in fluoride levels are linked to modification of the demineralization/remineralization balance by direct effects on the dental mineral. Plaque fluoride levels have been clinically correlated with dose response in providing anti-caries. Thus the fluoride pharmacokinetic reservoirs and the bioavailability of fluoride in saliva, and consequently in plaque fluid, play a crucial role in preventing a net mineral deficit. The source of the fluoride can also play an important role as the source used will lead to different salivary fluoride concentrations post brushing. Sodium monofluorophosphate (Na-MFP) requires hydrolysis to release free fluoride ions. The different dissolution properties can lead to different fluoride concentrations in plaque, consequently affecting the caries protective effect of plaque fluoride content. The fluoride binding to the plaque reservoirs and the release from the reservoir is a complex multi-mechanism; binding to the anionic sites on the bacterial wall, within the plaque matrix constituents via calcium bridging, binding to calcification nuclei or diffusion kinetics based on the specific plaque matrix.
Basic amino acids, such as arginine bicarbonate, are well known for their benefits combating cavity formation, and/or tooth sensitivity; and/or providing pH neutralizing effects.
However, at least some commercialized dentifrice products having arginine bicarbonate have less than optimized fluoride uptake. Accordingly there is a need to for high water (e.g., >44 wt %), high carbonate (e.g., >24 wt %), fluoride ion source, basic amino acid containing dentifrice compositions having improved fluoride uptake in dental plaque.